title: Phylogenetic position of the saola (Pseudoryx nghetinhensis) inferred from cytogenetic analysis of eleven species of Bovidae.
abstract: Previous morphological and molecular analyses failed to resolve the phylogenetic position of the critically endangered saola (Pseudoryx nghetinhensis) with respect to its placement in Bovina (cattle, bison, and yak) or Bubalina (Asian and African buffaloes). In the present study, G- and C-banding, Ag-staining and FISH with 28S and telomeric probes was undertaken for 17 bovid species. An analysis of these data allowed us to identify 49 structural rearrangements that included autosomes, gonosomes and 17 different NOR sites. The combined data set was subjected to a cladistic analysis aimed at: (i) providing new insights on phylogenetic relationships of the saola and other species within the subfamily Bovinae, and (ii) testing the suitability of different classes of chromosomal characters for phylogenetic reconstruction of the family Bovidae. The study revealed that nucleolar organizing regions (NORs) are phylogenetically informative. It was shown that at least one, or sometimes two of these characters punctuate divergences that include nodes that are the most basal in the tree, to those that are the most recent. In this context, the shared presence of three NORs in saola and species of Syncerus and Bubalus strongly suggests the saola's placement within the subtribe Bubalina. This contrasts with Robertsonian rearrangements which are informative only at the generic level. These findings suggest that NORs are an important and frequently overlooked source of additional phylogenetic information within the Bovidae that may also have applicability at higher taxonomic levels, possibly even for Pecora.
authors.affiliation: UMR 5202 - Origine, Structure et Evolution de la Biodiversité, Département Systématique et Evolution, Muséum National d'Histoire Naturelle, Paris, France.
authors.forename: T T
authors.initials: TT
authors.lastname: Nguyen
authors.forename: V M
authors.initials: VM
authors.lastname: Aniskin
authors.forename: M
authors.initials: M
authors.lastname: Gerbault-Seureau
authors.forename: H
authors.initials: H
authors.lastname: Planton
authors.forename: J P
authors.initials: JP
authors.lastname: Renard
authors.forename: B X
authors.initials: BX
authors.lastname: Nguyen
authors.forename: A
authors.initials: A
authors.lastname: Hassanin
authors.forename: V T
authors.initials: VT
authors.lastname: Volobouev
mesh_terms: D000818:Animals; D005075:Biological Evolution; D016164:Bison / Q000145:classification / Q000235:genetics; D002020:Buffaloes / Q000145:classification / Q000235:genetics; D002417:Cattle / Q000145:classification / Q000235:genetics; D002871:Chromosome Banding; D003582:Cytogenetics; D005260:Female; D006041:Goats / Q000145:classification / Q000235:genetics; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D008297:Male; D009697:Nucleolus Organizer Region / Q000235:genetics; D010802:Phylogeny; D012418:Ruminants / Q000145:classification* / Q000235:genetics*; D012756:Sheep / Q000145:classification / Q000235:genetics; D013045:Species Specificity; D014178:Translocation, Genetic; D014960:X Chromosome / Q000235:genetics